Diurnal, Nonsynchronous Rotation and Obliquity Tidal Effects on Triton using a Viscoelastic Model: SatStressGUI. Implications for Ridge and Cycloid Formation

David Dubois (1, 2) , D. Alex Patthoff (3, 1) , Robert T. Pappalardo (1)

1 JPL - Jet Propulsion Laboratory
2 PLANETO - LATMOS
3 PSI - Planetary Science Institute [Tucson]

Neptune’s biggest moon Triton orbits at an almost constant distance of about 355,000 km from its parent body. The satellite has a very low eccentricity (e = 10^-5), and rotates synchronously about Neptune. It is thought to have been differentiated enough for the formation of interior solid and even liquid layers [1]. Generally, diurnal tidal forcing is the main stressing mechanism a satellite with a sufficient eccentricity can experience. Other possibly combined sources participating in the tidal evolution of a satellite can be nonsynchronous rotation (NSR), axis tilt (obliquity), polar wander, and ice shell thickening. Given Triton’s current very low eccentricity, the induced diurnal tidal forcing must be relatively non existent. Triton’s eccentricity has most likely changed since its capture [2] and this change in eccentricity may account for the formation of surface features and maintaining a subsurface liquid ocean [2, 3]. Furthermore, obliquity induced tides have been shown to play a role in Triton’s recent geological activity [1] with its high inclination. Thus, modeling Triton’s tidal behavior is essential in order to constrain its interior structure, tidal stress magnitudes, and surface feature formation.

Domaines: Planétologie

David Dubois, D. Alex Patthoff, Robert T. Pappalardo. Diurnal, Nonsynchronous Rotation and Obliquity Tidal Effects on Triton using a Viscoelastic Model: SatStressGUI. Implications for Ridge and Cycloid Formation. 48th Lunar and Planetary Science Conference, Mar 2017, The Woodlands, TX, United States. ⟨hal-01467344⟩